The compound (+)-isomer of .alpha.-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemeth anol is generically described by U.S. Pat. No. 5,169,096 and specifically described in U.S. Pat. No. 5,134,149, both of which are hereby incorporated by reference. This compound is described therein as a 5HT.sub.2A receptor antagonist. It has since been discovered that this compound is useful in the treatment of Depressive Disorders and Bipolar Disorders.
The compound of the present invention solves the complicated problem of treating patients for Depression Disorders or Bipolar Disorders through an unusual compound profile. It is a highly selective 5HT.sub.2A receptor antagonist having subnanomolar affinity for the 5HT.sub.2A receptor versus affinities of greater than 100 nM for the 5HT.sub.2c, D.sub.1 (dopamine), D.sub.2 (dopamine), and .alpha.-1 receptors in in vitro models.
It has a lower affinity for receptors often associated with unwanted side effects, e.g., lower affinity for the D.sub.2 receptor suggests less potential to cause extrapyramidal side effects, little affinity for the cholinergic M1/M2 receptors suggests less cholinergic side effects such as dry mouth, delirium and cognitive impairment. It is orally active, non-toxic at therapeutic doses and potent. It is also capable of being scaled-up for commercial synthesis. Additionally, neurochemical studies indicate that there is a serotonin/dopamine interaction following chronic administration of this compound as described in Life Sciences 56(25): 2209-2222 (1995), incorporated herein by reference. The combination of the foregoing characteristics produces a unique compound for treating patients having either Depressive Disorders or Bipolar Disorders.